Socket for electron tubes



Dec. 19, 1961 c. P. WERNER SOCKET FOR ELECTRON TUBES ATTORNEY 4Sheets-Sheet 1 INVENTOR CARLTON P. WERNER BY $1M Filed April 9, 1957ill-2115!:

Dec. 19, 1961 c. P. WERNER SOCKET FOR ELECTRON TUBES 4 Sheets-Sheet 2Filed April 9, 1957 INVENTOR CARLTON RWERNER JMM ATTORNEY Dec. 19, 1961c. P. WERNER SOCKET FOR ELECTRON TUBES 4 SheetsSheet 3 Filed April 9,1957 INVENTOR CARLTON P. WERNER ymm ATTORNEY Dec. 19, 1961 c. P. WERNERSOCKET FOR ELECTRON TUBES Filed April 9, 1957 F l G '9 4 Sheets-Sheet 4FIG.

371 ig OUTPUT RFC w m 3 M Y & OE FE j Tw N N. R EP 0 MN n T m U A J w CBU n 3 L 2 L C F I z 2 C 5 \|I\2 O C 1 T Design Services, Inc, Hanover,N.J., a corporation of New Jersey Filed Apr. 9, 1957, Ser. No. 651,730

' 21 Claims. (Cl. 339-182) This invention relates to socket devices forelectron discharge tubes and, more particularly, to such of a specialtype having a plurality of axially spaced electrodes in coaxial relationwith one another with heater contacts at one end.

The tube for which the embodiments of the present invention areparticularly designed in a triode, specifically one of a series of newceramic-titanium electron tubes. Such tubes are generally of themicro-miniature, ceramic receiving tube type, one designated 6BY4 by theGeneral Electric Company, having been developed as a low-noise, high-mutriode for UHF-VHF television receivers. This one is about 7 long and indiameter, although I do not wish to be limited to the exact type orexact size.

However, the socket to which the present invention particularly relatesis for a tube in which there are three short cylindrical contactelements respectively spaced by ceramic insulators which project beyondthe cylindrical surfaces of the electrodes, a third insulator beingdisposed at one end of one electrode and carrying a pair of buttonshapedcontacts on an exposed fiat face, said contacts being suitable forsupplying power to a'cathode heater element therein. Thus the tubeinvolves narrow cylindrical contacts for respective connection with theplate or anode, the grid, the cathode, and end button contacts for thecathode heater.

An object of my invention is to provide a socket for a tube ofrelatively small size, producible at low cost by mass productionmethods, from which the tube is readily removable, which is easilymounted on a chassis, having excellent shock and vibration resistance,having floating contacts for the cathode, grid, and plate elements ofsaid tube, and fixed contacts for the heater elements thereof, in orderto allow formanufacturing variations in the concentricity and diameterof the peripheral surfaces of the tube elements, so that a goodelectrical contact to said tube elements will be maintained under allconditions.

Another object of my invention is to provide a socket having fixedcontacts for the two heater buttons of the tube so that adequate contactpressure will be maintained under all conditions of dimensionaltolerances, and in which the tube may beeasily inserted and removed.

A further object of my inventionis to provide a socket having arelatively large contact area with respect to the cathode, grid andanode elements of the tube, while having'such contact areaior each ofsaid elements at a minimum in a plane parallel to the adjacent element.

' A still further object of my invention is toprovide a socket'havingheater "contacts designed to prevent the tube from'being inserted in amanner which will short out the heater circuit, and thereby preventinsertion of the tube in any position'but the correct one.

An additionahobject of my invention is to provide a socket having'aninsulating member made of a material which will withstand normally softsoldering temperatures without softening or distorting, will functionunder conditions of high humidity, high and low temperatures, which willstand extremeconditions of-fshock and vibration, in which the materialof the insulating member exhibits characteristicsof low loss,'lowdissipation, low dielectric constant, high dielectric strength, and lowmoisture absorption, and in which the carried contacts are silver platedfor high surface conductivity, whereby socket but it is suitable foroperation in circuits carrying current at ultra high frequencies.

Another object of my invention is to provide a socket for groundedgridcircuits having the above-mentioned features and, in addition,having a metal shield between the cathode and the anode, said shieldbeing constructed so as to serve as the grid contact as well as theshielding means, in which the grid contact has interlocking leaves whichclamp around the periphery of the tube grid element and make relativelylarge area contact around the periphery of said element, and in whichthe clamping means of the grid contact assembly will prevent the tubefrom becoming dislodged under conditions of extreme shock or vibration.

A further object of my invention is to provide a socket forgrounded-grid circuit use, in which the clamping means of the gridcontact assembly is readily releasible for easy removal of the tube fromthe socket.

These and other objects and advantages will become apparent from thefollowing detailed description when taken with the accompanyingdrawings. It will be understood that the drawings are for purposes ofillustration and do 'not define the scope or limits of the invention,reference being had for the latter purpose to the appended claims. 1 i IIn the drawings, wherein like reference characters denote like parts inthe several views:

FIGURE/l is an isometric view of a preferred .embodiment of a socketincorporating my invention. 7 FIGURE 2 is a side elevational view of theembodiment of FXGURE l, with an electronic tube held therein. FIGURE 3is an end elevation-s1 view'of the socket and tube shown in FIGURE 25IGURE4 is a fragmentary longitudinal vertical sectional view on thelineiV-IV of FIGURE .l,"-in the direction of the arrows, showing, astypical of one of the anode, grid and cathode contacts, the grid contactfloating in the insulating base.

FIGURE 5' is a fragmentary vertical sectional view on the line VV ofFIGURES 1 and 2, in the direction of the arrows of the contact of FIGURE4. Y

FiGURE 6 isa fragmentary longitudinal vertical sectional View on theline VlVI of-FIGURES 1 and 3, in the direction of the arrows, showingthe lefthand heater contact, as viewed'in said figures, and 'how itis-locked in place with respect to the insulating base.

FIGURE 7 is an isometric view corresponding to FIGURE 1, but showing theinterlocking leaf members of the 'grid contact inclosed or engagedposition-in a modification to make a grounded-grid contact assembly.FIGURE-8 isanisometric' view 'of the same-socket, but from a directionapproximately at right angles to that ofFlGURE 7, showing theinterlocking leafmembers of the grid contact in open or releasedposition?- FIGURE 9 is a plan of another embodiment of the inventionpinwhich there is ashield mounted'over the k t. j I. FIGURE 16 is a sideelevational view of the embodi- FIGURE 11 is an end elevational view ofthe embodiment of FIGURE9. i I FIGURE '1'2-is a side elevational view ofthe same with another design of shield mounted-therev' 1 j' r jj.

"FIGURE 13 is an end elevational view of the socket and shield of FIGURE12.

FIGURE '14 is an isometric view corresponding to FIGURE 7, but showinganother embodiment of my invention. i FlGURE 15 is an isometric View ofthe same socket, but from a direction approximately at right angles tothat 3 of FIGURE 14, showing the two pivoted grid contact members inopen or released position.

FIGURE 16 is an isometric view corresponding to FIGURE 14, but showinganother embodiment of my invention.

FIGURE 17 is an isomeric view of the same socket, but with the uppergrid contact member raised above its normal or interleaved position withrespect to the lower grid contact members.

FIGURE 18 is an elevational view of a side of the separator or fillermember which is sandwiched between the plates forming the lower memberof the grounded-grid contact assembly of the embodiment of FIGURES L6and 17. 7

FIGURE 19 is a plan of a modified form of base insulator, improved insome respects as compared with that shown in the preceding embodiments.

FIGURE 20 is a side elevational view of the base insulator of FIGURE 19.

FIGURE 21 is an elevational view of a side of a modified form of therighthand heater contact, as viewed in FIGURES l, 3, 7, 8, ll, 13, 14,15, 16 and 17 from the opposite direction.

FIGURE 22. is an elevational view from the right of an edge of the formof contact illustrated in FIGURE 21, a fragmentary portion of anassociated base insulator being also shown.

FIGURE 23 shows a typical circuit suitable for use i with a socket suchas shown in FIGURES 7 and 8.

FIGURE 24 illustrates a tuned grid, tuned plate circuit which is typicalof one in which could be used the embodiment of the socket shown inFIGURE 1.

FIGURE 25 is a fragmentary side elevational view corresponding to FIGURE2, but omitting the electronic tube and showing another embodiment of myinvention.

Referring now to the drawings in detail and first considering theembodiment of my invention illustrated in FIGURES 1 to 6, inclusive,there is shown a socket 21 comprising a base insulator 22, desirablythicker at its ends than intermediate thereof, so that the lower surface20 of its intermediate portion is upwardly oflFset, as shown mostclearly in FIGURE 2. Received in longitudinallyspaced but staggeredslots or apertures 60 in said insulator 22 is a series of threelongitudinally aligned electrode contacts, here comprising a cathodecontact 23 or one adapted to connect with the cathode of a supportedtube, a grid contact 24 one adapted to connect with the grid of asupported tube, and an anode contact 25 or one adapted to connect withthe anode or plate of a supported tube, and transversely alined heatercontacts 26 and 27 or one adapted to connect with the cathode heater ofa supported tube. formed as identical metal stampinigs. Heater contacts26 and 27 are desirably formed as left-hand and righthand metalstampings having the same outline dimensions.

The grid contact 24 of the three identical contacts 23, 24 and 25 isinserted into the intermediate slot 60 in the base insulator 22 in theopposite direction, that is, after it has been reversed face-to-face, orturned 180 about its vertical axis, as compared with the cathode contact23 and the anode contact 25. This reversal approximately doubles thedistance separating the stems of any adjacent two of the three contacts23, 24 and 25, thereby correspondingly reducing the capacitance betweensaid stems, while still leaving the bifurcated upper portions uniform,parallel and registering with respect to one another. This arrangementthus results in a very low capacitance between the. grid contact and thecontacts on either side thereof, that is, the cathode and the anodecontact, while at the same time permitting the use of identical metalstamping contacts for lowest possible cost.

The heater contacts 26 and 27 are provided with laterally oifset areashere illustrated as upper adjacent corner portions 28 and 29, for directleftand right-hand electrical contact, the upper edge portions of whichare desirably bent outwardly at an angle of about 20 (as indi- Contacts23, 24 and 25 are desirablycated by the reference character 81 inFIGURES 21 and 22), to facilitate tube insertion. These offset portionsare also longitudinally offset to create adjacent steps in which theheater contact buttons of a supported electron tube or triode 50 arenestingly receivable. The provision of these steps prevents the tubefrom being inserted in such a manner, such as with one heater buttonabove the other, as would short out the heater circuit.

The following is a description of only one form of electron tube 50which may be supported in a socket embodying my invention, but is notintended as a limitation on said socket. The General Electric Company ismanufacturing a ceramic high-mu triode of parallel plane construction,designed primarily for use as a grounded-grid radio frequency amplifierin combined UHF-VHF tele vision tuners. It is designated as the 6BY4. Insuch service, at 900 megacycles, the tube exhibits a power gain ofapproximately 15 decibels and a noise factor of approximately 8.5decibels with a 10-megacycle bandwidth.

The small size of the 6BY4 makes it particularly suited to compact tunerdesigns. I have invented the socket here described and claimed, which isone of the special clip or friction type, and is particularly adapted tohold such a tube. The special metal/ceramic construction of the 6BY4tube makes it possible to operate it at much It has increasedresisthigher envelope temperatures. ance to mechanical shock andvibration, as well as greatly increased physical strength, and producessignificantly lower microphonic output.

The embodiment illustrated comprises three ceramic insulators 54, 55 and56, which respectively separate the heater contact buttons 30 and 40 atthe righthand end, as viewed in FIGURE 3, from the cylindrical disccathode contact 57, the latter from the cylindrical disc grid contact52, and the latter from the cylindrical disc plate or anode contact 58.The ceramic insulators may be .100" thick and .323" in diameter, whilethe heater buttons may axially project .022" and be .090 in diameterwith their centers spaced .120". The relatively thin cathode and gridcontacts may each be .025" thick, and the plate contact may be .050thick. All of said cylindrical cathode, grid and plate contacts may be.285 in diameter.

The cathode contact 23, the grid contact 24 and the anode contact 25 arefloating in the base insulator 22, as illustrated most clearly inFIGURES 4 and 5. By this it is meant that there is a base side space 31,which may be .002 as a typical dimension, formed at a side of thecontact to allow it to move slightly in the receiving slot 60 in theinsulator 22. There is also a base edge space 32 provided, asillustrated in FIGURE 5, .004 being a typical dimension for this, whichallows a corresponding amount of motion transversely of the insulator22. Corresponding vertical motion is allowed for by a space 33, whichalso may be .004 as a typical dimension. FIG- URES 4 and 5, althoughbeing specific for the grid contact 24, also illustrate the constructionand connection'of the contacts 23 and 25, but viewed from oppositedirections. All of said contacts are, therefore, retained in the baseinsulator 22 by bending a lanced spring finger 34 out from the stem 35of the contact at least one material thickness, so as to underlie, andhold the enlarged upper portion of the contact in place on the fiatupper surface of, the base insulator 22. All of these contacts desirablyhave their stems 35 offset laterally from the bifurcated normally upperportions 42 a distance corresponding with the staggered distance betweenthe slots 60 so that, after insertion in the base, said upper portionswill be longitudinally alined and provided with notches 36, as shownmost clearly in FIGURES 4 and 5, for easy connection to associatedcircuitry.

The heater contacts 26 and 27 are locked securely with no free movementin the insulating base, as shown most clearly in FIGURES 3 and 6, asthese are each provided with a head 80, a stem 41 projectingtherebeneath, and a lanced spring finger 37 which is bent from the stemto press against a tapered surface 38 (except in the embodiment ofFIGURES 19 m 22, inclusive) defining a slot or aperture 39 whichreceives the stem 41 projecting down from the wider head 30 of theheater contact, and thereby holds said head in engagement with the topsurface of the insulator 2'2, and prevents the contact from movinglaterally or vertically upward. These contacts, therefore, do not floatin any direction, because they snugly fit the slot 39 at its normallyupper end.

As will be clear from a consideration of FIGURE 5, the radius R of theinner edge of the bifurcated part here shown as the upper part of thecontact 24 which receives the corresponding short cylindrical contactelement 52 of the tube 50 when held therein, has its inner end upwardlyoffset from the inner end 54 of the radius R of the outer edge of saidbifurcated part, so that the curved beam 42, so defined, hasapproximately uniform stressover-strength characteristics. Suchconstruction makes the bifurcated, nearly semicircular portion 42 of thecontact 24 stiffer at its lower section, where it abuts the ind thesemicircular portion 42 of the contact 24 to yield or o expand when thetube 50 is inserted in it. The contact yields a. greater amount at theupper or open ends, where the cross section of the material is less, anda lesser amount at the lower end, where the cross section of thematerial is greater, thereby permitting the inner surface of the contactto establish a large area, low impedance engagement with the outerperiphery of the tube contact 52 when the tube is held therein.

The generally semicircular portions of the contacts 23, 24 and are on anare slightly greater than 180 so that the distance across the open orrounded ends is less than D As a result the tube 50 when positioned forsupport, as shown in FIGURES 2 and 3, must be forced past these upperend portions 43 and 44 of all of said contacts, and when past, said tubeis held rigidly in place against possible forces of shock or vibration.

Dimensions for the embodiment of my socket previously described whichare suitable for the 6BY4 tube are as follows, it being understood thatthese dimensions are illustrative and not limiting. The base insulator22 is desirably formed of compression molded material having lowdielectric loss for ultra high frequency power and preferably notaffected by temperatures up to 400 F.

However, the following specific materials are mentioned aspossibilities: For a medium temperature (up to 400 F.) Plaskon AlkydMolding Compound 446, manufactured by Barrett Division of AlliedChemical & Dye Corporation, may be used. For higher temperatures (up to500 F.) a glass-filled silicone molding material known as BakeliteGMKA-5004 manufactured by Bakelite Company, a division of Union Carbonand Carbide Corporation; or Dow Corning 301, a similar materialmanufactured by Dow Corning Corporation, may be used. In the mediumtemperature range (up to 350 F.) another good selection would be aDiallyl Phthalate known as Diall 5220-30 and manufactured by MesaPlastics. All of these are thermosetting plastic material filled withglass fiber for high impact strength.

The next higher temperature range (up to 750 F.) would require aformulation of high-temperature electrical glass and synthetic micaknown as Supramica 555 manufactured by Mycalex Corporation of America.Other formulations of high-temperature electrical glass and powderednatural mica, such as Mycalex 410, may also be used in this temperaturerange.

The highest temperature range (up to 1000 F.) would 6 require a ceramicmaterial. Steatite, chiefly clinoenstatite crystals MgO.SiO known asAlsimag 196, could be used. A 95% alumina A1 0 known as Alsimag 614, hasa higher impact strength and would be preferred for temperatures up to1000 F. Either of these materials has a softening temperature above 2500F., but the socket use would be limited to 1000. F. because of thematerial used for the spring contacts.

The insulator desirably has an overall length of /3", a width of 5 andwith a distance of .687" between the holes 59 which are desirablyprovided for receiving securing means. ese holes may be .094" indiameter. The insulator 22 is desirably .140 thick at the apertured endportions and .125" thick therebetween and at the center. The slots forrespectively receiving the contacts 25 and 27, 24 and 25, all of whichare desirably constructed from beryllium copper about .020 thick heattreated and heavily silver plated, are spaced between centers, inagreement with the spacing of the tube contacts, .125", .125" and .130".

The lateral spacing of the apertures for receiving the contacts 26 anad27, of course agrees with the spacing of the heater buttons 30 and 40,so that their offset portions are adapted to receive these buttons whenproperly placed, but not allow the tube to seat when the buttons are notproperly placed as, for example, being one above the other. This meansthat when these contacts 26 and 27 are formed of a maximum width of.172", a stem width of .110, and a height above the stem of .245, theapertures for receiving these stems are positioned with adjacent endsspaced'laterally .096", and desirably set .225

from the adjacent end of the base insulator.

The portion desirably offset .015 at an upper corner of each contact,for receiving the corresponding heater button, is .094 wide and .108"deep. This offset portion has a comer rounded about a .050" radius, thatis, just a very small amount greater than the radius of the but tonwhich is received therein. Other dimensions may be determined byscaling.The upper edge of the offset portion of each of the contacts 26 and 27is desirably flared slightly outwardly, or toward the adjacent end ofthe base insulator, for, say, an additional .015", at an angle ofapproximately 20 to facilitate insertion of the tube 50.

Each of the other contact members, 23, 24 and 25, desirably has similarstem portions so that the stems of all of the contact elements, whenassembled, project to a uniform level below the base insulator 22, asviewed in FIGURES l, 2 and 3. These stems, however, are offset from thecenter-line of the bifurcated upper porticn of the contact, so thattheir inner edges are desirably about .021" from said center line.

The radius of the inner edge of said bifurcated portion is desirably.135, which, as will be noted, is a trifle less than that of thecylindrical tube contacts to be engaged therein. The radius of the outersurface of the 1 bifurcated or curved beam portion 42is desirably .172,

the normal diameter of .270. That means that in placing the tube in thesocket it has to be forced past these upper portions to spread them.015" before it snaps past them to be resiliently gripped in seatedposition.

in the modified embodiment of the socket illustrated in FIGURES 7 and 8,the grid contact 24 has been replaced by a grounded grid contactassembly 24a, but the socket 21a may be otherwise identical with that ofFIGURES 1 to 6, inclusive. The grid contact assembly 24:; is made up ofa saddle member 45, a plate member 46, and two cooperating interlockingleaf members 47 and 48, pivoted on the saddle member 45 as at 49 and 51respectively.

The leaf members 47 and 48 are desirably formed as identical metalstampings, reversed face-to-face as they are assembled, and eachdesirably of one-half the thickness of the saddle member 45. To insert atube, the leaf member 47 is swung up and clockwise to the position ofFIGURE 8 and the leaf member 48 is swung up and counterclockwise, alsoto the position shown in FIGURE 8. The tube is then inserted and saidsube will be held in its downward or nested position by the holdingforces of the cathode cont-act 23a and the anode contact 25a, which maybe identical with the contacts 23 and 25 of the first embodiment. Thenthe leaf member 47 isswung about its pivot 49 in a counterclockwisemotion and pressed downward over the tube body until it yields and locksover the cylindrical grid contact 52 of the tube 50. Next the leafmember 48 is swung about its pivot 51 in a clockwise motion and presseddownward over the tube body until it yields and locks over the samecylindrical grid contact 52 of the tube.

The diameter of the leaf members 47 and i8 is made for an interferencelit with the tube grid contact 52. Moreover the arc of contact isgreater than 180 so that the distance across the open ends is slightlyless than said leaf member diameter, as in the case of the bifurcatedupper end portions of the contacts 23, 24 and 25. As a result, the leafmembers will yield and lock around the periphery of the grid cont-act52. The plate member 46 is fastened to the two legs 61 and 62 of thesaddle member l5, which legs extend downward through slots (such asindicated at 6% in FIGURES l9 and 20) in the base insulator 22a, as bymeans of eyelets, rivets or similar fastening means as, or by spotwelding. A space 33a, which may be .004" as a typical dimension, ismaintained between the upper edge of plate member 46 and the bottomsurface of the base insulator 22a to permit the grid contact assembly24a to move vertically in the base insulator 22a. The two legs of thesaddle member 45 are thinner than the slot opening and narrow than theslot width provided in the base insulator 22a by typical dimensions of.002" and .004", respectively, like the clearances provided for thecontacts 23, '24 and 25 of the first embodiment, to permit the gridcontact assembly 24a to float in the base insulator.

FIGURES 9, l and 11 illustrate a preferred form of a socket embodying myinvention but with a downwardly opening shield mounted thereover. Theshield 64 is held in position by lips 65 and 66 which extend under theside edges of the base insulator 22b. Prongs 67 which eX- tend from thetwo lips will press against the surface on which the socket is mountedand establish a ground contact for the shield. Two upwardly extendingarms 68 and 69 are for the purpose of mounting and demounting the shield64, which may be done by exerting finger pressure to force the two armstoward eachother at their upward ends.

The elasticity of the shield 64 which may be made of a spring temperedsteel, for example, will spread the upwardly extending arms when thefinger pressure is relaxed, and cause the two lips 65 and 66 to movetoward each other.

FIGURES 12 and 13 illustrate a preferred form of a socket embodying myinvention but with another design of shield mounted thereover. Theshield 64c is held in position by a lip 65c which extends under one edgeof the base insulator 22c, and by a lip 66c which is provided with ahole for a machine screw or other holding means. The lip 66c is held incontact with the surface on which the socket is mounted and serves toestablish a ground contact for the shield as well as to retain theshield in position over the socket.

In a modified embodiment of the socket as illustrated in FIGURES 14 and15, the grid contact has been replaced by a grounded-grid contactassembly 24d, but the socket 21d may be otherwise identical with that ofFIG- URES 1 to 6, inclusive. The grid contact assembly is made up of asupport member 71, a saddle member 45d which unites the upstanding sidearms of said support member and between which the base insulator 22dfits, and two contact members 47d and 43d pivoted on said arms 70 at49c! and 51d, respectively. Contact members 47d and 48d are identicalmetal stampings. To insert a tube 50, the contact members are raisedfrom their closed positions as shown in FIGURE 14 to an open position asshown in FIGURE 15. The tube is pressed downward between the contactmembers 47d and 48d and as it moves downward contact member 48d turnsclockwise and contact member 47d turns counterclockwise until they reachthe closed position shown in FIGURE 14-, with the grid contact 52 of thetube securely locked within the periphery created by the curved edgesurfaces of the parts 45d, 47a and 48d. The radii of these three curvedsurfaces are made slightly less than the radius of the grid contact 52of the tube 56, thereby creating six high pressure areas in contact withthe periphery of said grid contact.

The pivots 49d and 51d are located on a line slightly above thecenterline of the opening created by the curved edge surfaces of theparts 45a, 47a. and 48d, so that a natural locking force is present whenthe tube is in position. The saddle member 45d has two legs 61d and 52dwhich extend through slots in the base insulator 22a, and these legs arefastened to the support member '71 by means of eyelets, rivets,spot-welding, or other fastening means 63d. A space 33d, which may be.004 as a typical dimension, is maintained between the lower edge ofsaddle member 45d and the upper surface of base insulator 22d to permitthe grid contact assembly 24 d to move vertically in the base insulator22d.

The two legs 61d and 62d of the saddle member 45d are thinner than theslot opening and narrower than the slot width provided in the baseinsulator 22d by typical dimensions of .002 and .004 respectively, topermit the grid contact assembly 24a to float in the base insulator.

Referring now to the embodiment of my invention illustrated in FIGURES16 to 18, inclusive, there is shown a further embodiment of the socketwhich provides excellent isolation of the input and the output withrespect to each other. Here the grid contact has been replaced by agrounded-grid contact assembly 242, but in which the socket 21:: may beotherwise identical with that of :FlGURES 1 to 6, inclusive. The gridcontact assembly 24e comprises two relatively-thin (such as about .010thick) shield plates 712, forming a support member, which are slippedover the ends of the insulator 222. Between the plates 716, afterassembly with the insulator 22a, is sandwiched a separator or filler andsaddle member 45a and to which said plates are secured as by beingspot-welded in four places, such as those designated 72. The saddlemember 45s forms a lower contact portion for the cylindrical gridcontact member 52 of a tube such as that designated 50, which may beheld in said socket and has the same interference fit with respectthereto as the cathode and anode contacts, 23c and 25s, respectively,thereby insuring a low impedance connection between said tube gridcontact element 52 and the grounded potential. Completing the contactassembly is an upper contact element 73 which is loose, in that it isnot pivoted or otherwise positively connected to the other members, butis slidable with respect thereto between the position of FIGURE 17 andthat of FIGURE 16, to thereby release or hold an associated grid contactmember 52 of a tube in place, as in the preceding grounded-gridembodiments.

This loose member 73 has a pair of depending arms 77 desirably formedwith arcuately outlined tips 78 which lock over sidewarclly-extendingarcuately tipped prongs 7d of the filler and saddle member 45c, andengages the cylindrical grid contact element 52 of a tube 59 around thetop part of its periphery, thereby adding to the shielding.

away from those of the other shield plate to conveniently guide the topmember into position. A flange 75 is desirably provided along the upperedge of the loose member 73 to facilitate holding it during movement toand from tubecontacting position.

The filler member 45: desirably has a pair of legs tile and 6242 whichare inserted through slots (such as indicated at 69] in FIGURES l9 and20) in the base insulator 222. After such insertion, the plates 71a aresandwiched thereover on opposite sides and spot-welded in place aspreviously mentioned. The same amount of clearance is desirably allowedbetween this grounded-grid assembly 242 and its insulator 22e as thereis between the grounded-grid assemblies of FIGURES 7, 8, l4 and 15 andtheir base insulators 22a and 22d, so that all are floating to an extentequivalent to t. at of the grid contact 24 of the first embodiment.

Referring now to the embodiment of FIGUREQ l9 and 20, there is discloseda base insulator 22,1 which may correspond with the insulator 22 of thefirst embodiment, except that there are a pair of slots oil for thegroundedgrid contact assemblies of the embodiments of FIGURES 7, 8, l4,l5, l6, l7 and 18, rather than only one slot for a stem 35. stems ofmodified heater contacts, the right hand one of which, 2%, isillustrated in detail in FIGURES 2i and 22. The left hand heater contactcorresponds with the heater contact 27 of EEGURES l and 3, except thatit is modified to a similar extent like the contact 26f is modified ascompared to the contact 26.

This heater contact modification involves the provision of a slot 76desirably about .025 wide and which extends above the lance 37 and upinto the wide portion of the contact 25f. The narrow strip of metal leftat the side of this slot adjacent the companion contact (which, althoughnot illustrated, we can call 2'7 as it corresponds with the contact 27of the first embodiment,) is bent outwardly, as viewed in FIGURE 21. Ithereby broaden the portion of the contact which passes through theinsulator 22 that is, through one of the slots 39f therein. Beingresilient, this bent strip holds the contact from side motion in saidinsulator.

This improvement also permits the contact to remain tight underconditions of temperature change, in which said contact and insulatorexpand and contract at different rates. The insulator 22 iscorrespondingly changed, in that the two slots 3% have parallel sidesrather than being tapered, as shown in FIGURE 6 and indicated by thereference character 38. The lance 37 instead of projecting up into atapered portion, as viewed in said FIGURE 6, is now formed to abut thebottom surface of the insulator 22], and hold the head 80 in contactwith the top surface of said insulator, when the contacts are locked inposition as viewed in FIGURE 22.

Although the embodiment of FIGURES 19 to 22, inclusive, has beendescribed separately from the preceding embodiments, it will beunderstood that all of said preceding embodiments may have heatercontact prongs, as a preferred alternative, like those of FIGURES 21 and22, and slots 39 like those shown in FIGURES 19, 20 and 22, rather thanlike those of the first embodiment.

FIGURE 23 illustrates a typical grounded-grid circuit in which disclosedembodiments of the socket would be employed. FIGURES 7 and 8 illustrateone embodiment of the socket for which FIGURE 23 would be a typicalcircuit. FIGURES 14, 15, 16 and 17 illustrate other embodiments of thesocket for which FIGURE 23 would be a typical circuit. FIGURE 24illustrates a tuned grid, tuned plate circuit which is a typical circuitin which the embodiment of the socket as shown in FIGURES l to 6,inclusive, could be used. The sockets illustrated are correspondinglyreferenced and the circuit lettering is con ventional.

Referring now to the embodiment of my invention illustrated in FIGURE25, there is shown instead of a As a further change, the slots 39]receive the V socket comprising a base insulator separate fromassociated apparatus, one in which such an insulator is replaced by aterminal board, insulating chassis wall or door, or any other insulatingsupport member 22g of suitable qualities and thickness. Received in saidinsulator 22g is a series of electrode contacts, here comprising acathode contact 23g, a grid contact 24g, an anode contact 25g and heatercontacts 27g. Contacts 23g, 24g and 25g are desirably formed asidentical metal stampings, as in the embodiment of FiGU-RES 1 to 6,inclusive. Heater contacts 27g are desirably formed as left-hand andright-hand metal stampings having the same outline dimensions, also asin said first embodiment.

The grid contact 24g of the three identical contacts 23g, 24g and 25g isdesirably inserted into the insulator 22g in the opposite direction,that is, after it has been reversed face-to-face, or turned 180 aboutits vertical axis, as compared with the cathode contact 23g and theanode contact 253. This reversal reduces the area which lies in a planeparallel to the planes of the contacts on either side thereof and is inregistry therewith. This arrangement results in a very low capacitancebetween the grid contact and the contacts on either side thereoflHowever, such reversal is not necessary in this or other embodiments ifthe device is used only where maintenance of such very low capacitanceis not needed. The heater contacts 27g are desirably constructed likethose of the first embodiment. it will alsobe understood, thatcorresponding modification of the other embodiments may be efiected, ifdesired.

Having now described my invention in detail in accordance with therequirements of the patent statutes, those skilled in this art will haveno difficulty in making changes and modifications in the individualparts or their relative assembly in order to meet specific requirementsor conditions. Such changes and modifications may be made withoutdeparting from the scope and spirit of the invention, as set forth inthe following claims.

I claim:

1. A socket comprising a base insulator with aplurality oflongitudinally-spaced but staggered apertures and a pair oftransversely-aimed apertures, a plurality of electrode contactsincluding a plurality of longitudinally-spaced contacts and a pair oftransversely-aimed contacts correspondingly received in said aperturesand supported on said insulator, said longitudinally-spaced contactshaving bifurcated upper portions and depending stems laterally offsetfrom said upper portions.

- 2. The invention as recited in claim 1 in which the longitudinallyaligned electrode contacts are formed as identical metal stampings.

3. The invention as recited in claim 2, in which each of the saididentical metal stampings forming the longitudinally alined electrodecontacts has its bifurcated upper portion formed with an arcuate inneredge subtending more than a semicircle, the radius of said edge beingslightly less than that of the cylindrical contact of an electron tubefor which designed, whereby in inserting said tube said cylindricalcontact snaps past the upper ends of said bifurcated portion, tensingthe same to thereby insure a tight fit making good contact.

4. The invention as recited in claim 3, in which the elements formingthe bifurcated upper portion of each electrode contact taper from theirjunction with the contact stem to near their ends to insure the desiredexpansive action as the tube is inserted.

5. The invention as recited in claim 1, in which the stems of saidelectrode contacts are heldin place in the base insulator by each havinga lanced spring finger bent out therefrom so as to underlie the baseinsulator.

6. The invention as recited in claim 1, in which the electrode contactsare floating in the insulator, by having clearance between their stemsboth laterally and longitudinally of said insulator, and in which meansis provided on each stem for locking it in place in said insulator withclearance between said locking means andthe bottom surface of saidinsulator to allow for vertical floating action.

7 The invention as recited in claim 1, in which the intermediate of saidthree electrode contacts is formed as a grid contact assembly suitablefor being grounded and made up of a saddle member, a plate member, andtwo cooperating interlocking leaf members pivoted on the saddle member,said leaf members being formed as identical metal stampings reversedface-to-face as they are assembled, and of approximately one-half thethickness of the saddle member.

8. The invention as recited in claim 1, in which a downwardly openingshield is mounted over the socket, said shield being held in position bylips which extend under the side edges of the base insulator and prongswhich extend from the lips to press against the surface on which thesocket is mounted to establish. a ground contact, and an arm extendingupwardly from each side of said shield.

9. The invention as recited in claim 1, in which there is a downwardlyopening shield provided for said socket, said shield being held inposition by a lip which extends under one side edge of the baseinsulator and by a lip on the other side of said shield which projectsoutwardly therefrom and is apertured for receiving holding means.

10. The invention as recited in claim 1, in which each of saidtransversely-alined contacts has a head and a stem depending therefrom,and a slot is provided in each stem, leaving a strip of metal at oneside which is expanded to resiliently hold each contact tight in itsbase insulator.

11. In combination with a socket as recited in claim 1, an electron tubesupported in said socket, said tube comprising a plurality of ceramicinsulators which respectively separate two heater contact buttons at oneend from a cylindrical disc cathode contact, the latter from acylindrical disc grid contact, and the latter from a cylindrical platecontact, said cylindrical disc contacts being gripped in the bifurcatedupper portions of said longitudinally spaced electrode contacts, and theheater buttons respectively engaging said transversely alined contacts.

12. The invention as recited in claim 1, in which one of said pluralityof electrode contacts is formed as a grid contact assembly suitable forgrounding and made up of a support member which projects below the baseinsulator, a saddle member secured to said support member and disposedabove said insulator, and a pair of identical metal stampings formingcontact members pivoted on side arms of said support member whichproject above said saddle member.

13. The invention as recited in claim 1, in which one of said pluralityof electrode contacts is formed as a grid contact assembly suitable forgrounding and made up of a support member which projects below the baseinsulator, said support member comprising two shield plates withupstanding side portions between which the insulator is slidable, asaddle member sandwiched between said plates and secured thereto, saidsaddle member forming a lower contact portion for the cylindrical gridmember of an electron tube for which it is designed and having a pair ofsidewardly extending arcuately tipped prongs, and an upper contactelement completing the assembly, slidable between said two shieldplates, and having a pair of depending arms formed with arouatelyoutlined tips which lock over the sidewardly ex tending arcuately tippedprongs of said saddle member.

14. A socket comprising a base insulator with threelongitudinally-spaced but staggered slots and a pair oftransversely-aimed slots, a plurality of electrode contacts includingthree longitudinally-spaced identically constructed contacts and a pairof transversely-alined contacts correspondingly received in said slotsand supported on said insulator, said longitudinally spaced contactshaving bifurcated upper portions and depending stems laterally ottset tosuch an extent with respect to said upper portions, that when theintermediate of said three contacts has its stem inserted in the baseinsulator, when reversed face to face with respect to the electrodecontacts on either side thereof, the upper portions are in properlongitudinal register, whereby because the oft setting increases thedistance separating the stems of any adjacent two of saidlongitudinally-spaced contacts, a very low capacitance is providedbetween said adjacent electrode contacts, and said transversely-aimedcontacts having laterally-offset areas for direct leftand righthandelectrical contact, said areas being also oliset longitudinally withrespect to the insulator to nestingly receive contact buttons of adevice used with said socket to prevent the incorrect insertion of suchdevice, but otherwise similarly formed.

15. A socket comprising a base insulator with three longitudinallyspaced but staggered slots and a pair of transversely alined slots, apurality of electrode contacts including three longitudinally spacedidentically constructed contacts and a pair of transversely-alinedcontacts correspondingly received in said slots and supported on saidinsulator, said longitudinally spaced contacts having bifurcated upperportions and depending stems laterally offset to such an extent withrespect to said upper portions, that when the intermediate of said threecontacts has its stem inserted in the base insulator, when reversed faceto face with respect to the electrode contacts on either side thereof,the upper portions are in proper longitudinal register, whereby becausethe offsetting increases the distance separating the stems of anyadjacent two of said longitudinally-spaced contacts, a very lowcapacitance is provided between said adjacent electrode contacts, andsaid transversely-aimed contacts having laterally-offset areas fordirect leftand right-hand electrical contact, said areas being alsooffset longitudinally with respect to the insulator to nestingly receivecontact buttons of a device used with said socket to prevent theincorrect insertion of such device, but other wise similarly formed, thethree longitudinally-alined contacts being fioatingly received in theinsulator and the transversely-alined contacts being locked securelywith respect to said insulator.

16. A socket comprising a base insulator with three longitudinallyspaced but staggered slots and a pair of transversely alined slots, aplurality of identically constructed electrode contacts including threelongitudinally spaced contacts and a pair of transversely-aimed contactscorrespondingly received in said slots and supported on said insulator,said longitudinally spaced contacts having bifurcated upper portions anddepending stems laterally offset to such an extent with respect to saidupper portions, that when the intermediate of said three contacts hasits stem inserted in the base insulator, when reversed face to face withrespect to the electrode contacts on either side thereof, the upperportions are in proper longitudinal register, whereby because theoffsetting increases the distance separating the stems of any adjacenttwo of said longitudinally-spaced contacts, a very low capacitance isprovided between said adjacent electrode contacts, and said transverselyalined contacts having laterally-offset areas for direct leftandrighthand electrical contact, said areas being also offset longtudinallywith respect to the insulator to nestingly receive contact buttons of adevice used with said socket to prevent the incorrect insertion of suchdevice, but otherwise similarly formed and secured to said insulator byhaving their stems passed snugly through the corresponding insulatorappertures, which apertures expandingly taper from the points of entry,locking of said stems being effected, after insertion in the insulator,by bending out lanced spring fingers from the parts of said stems beyondsaid insulator to engage portions of said insulator defining saidtapered apertures, thereby also restraining said contacts from movinglaterally and vertically upward.

17. A socket comprising a base insulator with threelongitudinally-spaced but staggered slots and a pair of transverselyalined slots a plurality of electrode contacts including threelongitudinally-spaced contacts and a pair of transversely-alinedcontacts correspondingly received in said slots and supported on saidinsulator, said longitudinally spaced contacts having bifurcated upperportions and depending stems, floating in said insulator by havingclearance in the receiving slots both laterally and longitudinally, andmeans for locking said contacts in place in said insulator withclearance between said locking means and the bottom surface of saidinsulator to allow for vertical floating action.

18. A socket comprising a base insulator with threelongitudinally-spaced but transversely-staggered slots and a pair oftransversely-alined slots, a plurality of electrode contacts includingthree longitudinally-spaced identically constructed contacts and a pairof transversely-alined contacts, said pair of contacts beingcorrespondingly received in said transversely-alined slots and allcontacts supported on said insulator, said longitudinally-spacedcontacts having bifurcated upper portions and depending stems laterallyoffset to such an extent with respect to said upper portions that whenthe intermediate of said three contacts has its stem inserted in theintermediate of said three longitudinally-spaced slots of said baseinsulator, while reversed face to face with respect to the electrodecontacts longitudinally thereof, the upper portions are in properlongitudinal register, whereby because the offsetting increases thedistance separating the stems of any adjacent two of saidlongitudinally-spaced contacts, a very low capacitance is providedbetween said adjacent electrode contacts, and said transversely-alinedcontacts having areas laterally-offset from opposite sides for direstleftand right-hand electrical contact, but otherwise similarly formed.

19. A mounting socket for multiple contact electronic units comprising abase insulator with a flat upper surface, a plurality oflongitudinally-spaced but staggered apertures between said surfaces anda plurality of identical bifurcated electrical contacts longitudinallyalined along, disposed above the top of, and each with a stemtherebeneath laterally offset from its bifurcated upper portion tocorrespond with the aperture staggering and received in said apertureswith a lanced spring finger bent therefrom to underlie the bottomsurface of said base insulator to hold said bifurcated contact againstsaid flat surface and clearance between said stem and insulator to allowsaid bifurcated contact to float sufficiently to accommodateeccentricities in the construction without applying lateral loads uponthe unit.

20. A socket comprising a base insulator with threelongitudinally-spaced but staggered apertures, threelongitudinally-spaced flat identically constructed sheet metal contacts,the planes of said sheet metal being parallel to one another, withdepending stems correspondingly received in said apertures and supportedon said insulator, said longitudinally-spaced contacts having disposedabove said insulator, uniform bifurcated upper portions parallel to oneanother, each formed with an upper edge concavely curved about ahorizontal axis to mate with a cylindrical contact of an associateddevice, and their stems laterally offset to such an extent with respectto said upper portions that when the intermediate of said three contactshas its stem inserted in the base insulator,

when reversed face to face with respect to the electrode contacts oneither side thereof, the upper portions are in proper longitudinalregister, whereby because the offsetting increases the distanceseparating the stems of any adjacent two of said longitudinally-spacedcontacts, a very low capacitance is provided between said adjacentelectrode contacts.

21. A mounting socket for multiple contact electronic units comprising aflat elongated base insulator and three electrical contacts bifurcated,identically constructed of flat sheet metal, longitudinally alined withone another,

the bifurcated portions disposed above and resting on 1 the top surfaceof said insulator, mounted in parallel planes, each formed with an upperedge concavely curved about a horizontal axis to mate with a cylindricalcontact of an associated device, and with stems laterally offset onalternate of said planes, received in and passing though said insulator.

References Cited in the tile of this patent UNITED STATES PATENTS1,001,101 Marx Aug. 8, 1911 2,397,985 Schriefer Apr. 9, 1946 2,443,706Jansen June 22, 1948 2,514,562 Stickney July 11, 1950 2,529,502 Kelleyet al. Nov. '14, 1950 2,766,020 Woods Oct. 9, 1956 2,787,735 Scal Apr.2, 1957 2,807,790 Del Camp Sept. 24, 1957 FOREIGN. PATENTS 449,395 GreatBritain Dec. 27, 1935 OTHER REFERENCES Sylvania (publication), March1954, Proceedings of the I.R.E., page 38A.

